regmap: if format_write is used, declare all registers as "unreadable"

Using .format_write means, we have a custom function to write to the
chip, but not to read back. Also, mark registers as "not precious" and
"not volatile" which is implicit because we cannot read them. Make those
functions use 'regmap_readable' to reuse the checks done there.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 3c34526091da..b7198f57b69c 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -36,6 +36,9 @@ bool regmap_readable(struct regmap *map, unsigned int reg)
         if (map->max_register && reg > map->max_register)
                 return false;
 
+        if (map->format.format_write)
+                return false;
+
         if (map->readable_reg)
                 return map->readable_reg(map->dev, reg);
 
@@ -44,7 +47,7 @@ bool regmap_readable(struct regmap *map, unsigned int reg)
 
 bool regmap_volatile(struct regmap *map, unsigned int reg)
 {
-        if (map->max_register && reg > map->max_register)
+        if (!regmap_readable(map, reg))
                 return false;
 
         if (map->volatile_reg)
@@ -55,7 +58,7 @@ bool regmap_volatile(struct regmap *map, unsigned int reg)
 
 bool regmap_precious(struct regmap *map, unsigned int reg)
 {
-        if (map->max_register && reg > map->max_register)
+        if (!regmap_readable(map, reg))
                 return false;
 
         if (map->precious_reg)